Saber-Toothed Squirrel Lived Near Dinosaurs

Northern Patagonia was once home to a squirrel-like mammal with extremely long canine teeth, a petite 4 to 6-inch-long body, a narrow muzzle and a rounded skull, according to a paper in the latest issue of Nature.

You won’t see this critter stealing birdfood in your garden because it lived more than 100 million years ago when dinosaurs were still thriving. As you can see from the above image, dinos must have been no strangers to this saber-toothed animal that might have spent its days darting around columnar dino legs.

The discovery breaks a prior gap of about 60 million years in the fossil record for South American mammals.

‘Shieldcroc’ May Be Father of All Crocodiles

An enormous prehistoric crocodile-like creature called “Shieldcroc,” so named because of a shield-like bony plate on its head, could be the last common ancestor of animals related to crocodiles and alligators.

Shieldcroc lived during the Late Cretaceous approximately 93 to 99 million years ago. Its skull was discovered in continental freshwater deposits from what is now Morocco, and researchers think that modern crocs may have first evolved near the Mediterranean Sea.

But Shieldcroc then and now is capturing greater interest due to its hard-to-miss “shield,” a raised mound of tissue packed with blood vessels and likely covered by a thick sheath, similar to what is seen in the frill of horned dinosaurs. It might have helped to regulate body temperature, but probably served a flashier purpose.

Wither the Wolf, Behold the Coywolf

According to werewolf legends, some humans can suddenly “shapeshift” or transform into wolves. But in real life, wolves are disappearing in large numbers and being replaced by coywolves. These coyote-wolf hybrids are now common in parts of the U.S.

A new study in the Journal of Mammalogy proves that such interbreeding is taking place. Lead author Christine Bozarth of the Smithsonian Conservation Biology Institute and her colleagues collected coyote scat (aka poop) and conducted DNA studies on it. The DNA revealed that coyotes moving into Northern Virginia stopped along their route to breed with native Great Lakes wolves.

People are to blame for the coyotes moving in the first place, since the changes inflicted on North American ecosystems over the past 150 years, due to hunting, habitat encroachment, pollution and other causes, have pushed coyotes out of their native homelands of the plains and southwestern deserts. Now coyotes are on the move and seeking other places to live.

The poop trail left behind by the animals reveals that coyotes have been migrating eastward along two main routes — one through the South and another through the northern U.S. The new DNA information shows that Virginian coyotes are most closely related to coyote populations in western New York and Pennsylvania.

While trekking northward, they eventually encountered the Great Lakes wolves and interbred before converging again on the East Coast. They then gradually headed south along the Appalachian Mountains toward what is considered the Mid-Atlantic region, to an area centered around Virginia.

“The Mid-Atlantic region is a particularly interesting place because it appears to mark a convergence in northern and southern waves of coyote expansion,” Bozarth was quoted as saying in a press release. “I like to call it the Mid-Atlantic melting pot.”

Hybridization between canid species is thought to be rare, but as this latest study proves, it can occur. Hybridization may happen when individuals have trouble finding mates from their own species.

Submit an Article

Submit an article to The Noetic Digest by emailing katypress AT eircom.net
We will be happy to consider suitable content for inclusion.
Comments are welcome. However we ask that material for the comments section does not exceed 500 words.